S550 IRS in a S197

[Mustangdude72]

Anybody think it'll be done? if some could use the rear cradle from a wrecked s550 and make it work with a s197 platform, thoughs, ideas?

[rlhay2]

For what it would cost over and above a well setup Watts link, It is likely not worth it.

[Mustangdude72]

Originally Posted by rlhay2 For what it would cost over and above a well setup Watts link, It is likely not worth it.

True but for someone looking to do a lot of road racing and drifting as well as be an effective daily it might be worth the cost, im not gunna rule it out do to cost before i know if it can even be done in the first place, its just a though, coming from my terminator to the boss i kinda miss my IRS,

[G-Mann]

It might be done by someone with too much time and money on their hands but I don't see a market for this. If IRS becomes that important folks will upgrade into a 2015 vs spending the cash, maintenance, added weight, degraded mpg, degraded straight line performance. Not to mention the creaks and moans its going to add.

I think the SRA is a nice characteristic of the previous gen and even more so with a Boss 302. GT350 will be revealed soon and will be a legitimate Boss replacement with IRS.

[BlackStang08]

Dude, you have a Boss that is setup perfectly for the track and you want IRS? Yes wait for the GT350 or get a 2015.

[NDSP]

Probably won't work, because the track width is wider on the s550 than the s197 by over 2" I think. You'd end up hard pressed to put a decent sized wheel and tire without flairs. I've thought about putting in an irs in mine, but using the art Morrison IRS or Heidt's universal irs. I know the Morrison is available in three different widths. With either you are looking at $10k easy.

[Madlock]

The presumption that replacing an S197 live axle with an IRS necessarily will improve handling by default is wrong, especially as well-sorted as many S197 models' live axles are, even without Watts linkages or performance suspension configurations like an FR-3 pack helping them out.

An S197 IRS swap surely will change handling properties but not necessarily make them better or worse. Above all, the handling will be different. S550 is a perfect example. When Ford borrowed a Fusion IRS to use as a development boilerplate, one of the engineers' first discoveries was how unsuitable it made the carryover S197 front suspension they originally paired it with. They didn't eventually redesign the front suspension just to refine its performance with an IRS. Ford scrapped the S197 front suspension altogether because pairing it with an IRS initially made S550 handle worse.

Whether the goal is to create the best all-around balance of handling properties for a daily commute and occasional performance driving or the best, most aggressive handling for track only use, setting up a car's handling rarely comes down to just swapping out one component and calling the job done, no matter how limited a particular component's potential may be or how much more a different (or different type of) component may deliver.

What matters most is how all of the various suspension components work together to deliver a particular set of handling characteristics. This is one reason why Ford Racing historically has offered "handling packs" which can include everything from springs and dampers to bars and bushings that work together predictably rather than single parts like lowering springs which may lower the CG and stiffen the ride without compensating for the different bounce and rebound and sway and stabilizer properties that make the car handle as well as possible rather than tweaking one or two characteristics without regard to how well the car handles overall.

This kind of holistic approach is how Ford engineers were able to make the BOSS seem so planted and nimble. There's no one magic bullet. It's how all the pieces work together. An that remains the best way to improve S197 handling rather than just ditching the live axle because it happens to be the one piece that draws the most attention for being the oldest type of component that's used.

Rather than swapping out suspension types, or even a simple set of springs, the best way to improve handling is first to decide upon the specific handling goals you want a suspension to achieve and then assemble the components that work together best to deliver that combination of characteristics. Because replacing an S197 live axle with an IRS also would require a front suspension redesign or using an aftermarket complete suspension solution that centers on an IRS with all the other components to make it perform as well as possible, doing the job right and actually improving the car's handling usually is a very expensive from-the-ground-up propositon.

[NDSP]

My day dream build suspension wise would be a irs in back with an sla in the front. I have no idea if it would be great or crap, lol. This of course would be a art Morrison g-max frame, with my 2012 body on top all weighing in at 2500 lbs. a coyote with twins and a 7 spd dual clutch tranny. Might as well while I'm dreaming

[Lucky13]

Originally Posted by NDSP My day dream build suspension wise would be a irs in back with an sla in the front. I have no idea if it would be great or crap, lol. This of course would be a art Morrison g-max frame, with my 2012 body on top all weighing in at 2500 lbs. a coyote with twins and a 7 spd dual clutch tranny. Might as well while I'm dreaming

Dream big! I like it.

[Madlock]

Hell. For that kind of dough, you can buy a 911 turbo or GT3 and never need to worry about how to improve your car's handing ever again. And it might have some resale to boot!

[BlackStang08]

Madlock, you work for ford?